Insurgents learn to exploit U.S. military's vulnerabilities.

As insurgents continue to develop more lethal means to attack U.S. forces and allies in Iraq, both military and private security officials have been conducting briefings on how to recognize and avoid the ubiquitous threats of suicide bombs, roadside mines and ambushes.

According to a briefing crafted by Blackwater USA, one of the largest private military firms, insurgents have effectively exploited the vulnerabilities of U.S. military truck convoys. In one example, a gun team initiates an ambush, bringing the convoy to a halt. Terrorists draw fire to their side of the road while a second team detonates a bomb, attacking the convoy from the rear.

This ambush takes advantage of a convoy commander's tendency to fix attention on the direction of incoming fire. In a variation of the scenario, one team fires at the convoy while a rocket-propelled grenade team waits under cover, before firing at the rear vehicle and slipping away.

Alleyway ambushes also are common. An insurgent scout warns a gunman of approaching vehicles. The gunman then fires at the passing vehicle before escaping into a waiting car. This shoot-and-scoot tactic has been used in both rural and urban areas.

Insurgents also have staged car accidents as a ruse to attack U.S. troops and support forces, noted Blackwater experts who put together the "terrorist modus operandi" briefing. In such cases, the targeted vehicle is forced to stop because of a staged accident. A crowd gathers, hemming in the target vehicle. On command, the crowd parts allowing gunmen to fire before escaping into a waiting vehicle. This tactic also has been used against security forces vehicles and personnel responding to the accident. The insurgents' use of the crowd limits the coalitions ability to return fire, because of concerns over civilian casualties.

Rolling ambushes also are a favored tactic of the Iraqi terrorists. Gunmen hidden in an overlooking vantage point initiate the ambush. Meanwhile, a blocking vehicle moves behind the convoy. Roadside gunmen then rake vehicles as they pass, while the blocking vehicle veers in front of the convoy to prevent escape.

Drive-by shootings and attacks from overpasses are common methods employed by the Iraqi insurgents. The terrorist follows a target vehicle, and then at an opportune moment overtakes it and fires at it while the hostile vehicle passes.

Over time, Iraqi insurgent forces have adopted a steadily more sophisticated mix of tactics, including manipulating the media, linking asymmetric warfare to crime and looting, and relying on methods of attack that provoke a disproportionate amount of fear and terror, said Anthony Cordesman, an expert with the Center for Strategic and International Studies.

At the same time, the Pentagon has been scrambling to find solutions to defeat the improvised explosive devices, or IEDs. The Air Force, for example, is relying on electronic-warfare systems aboard fighter jets to set off IEDs along Iraqi roads, said Brig. Gen. Allison A. Hickey, assistant deputy director of strategic planning on the Air Staff. These EW technologies--traditionally used to disable enemy air defenses--also can jam wireless doorbells or cell phones that insurgents employ to detonate bombs.

But while technology can provide solutions and partly alleviate the problem, it is more important to understand how the insurgency works and adjust tactics, said Ben Riley assistant deputy undersecretary of defense for force protection.

"The IED is a symptom, but we need to treat the insurgency problem," he said. That means the U.S. military needs to relearn counter-insurgency warfare, he stressed in a presentation to industry.

Insurgents have been using a mix of crude and sophisticated IEDs, said Cordesman. "Hezbollah should be given credit for having first perfected the use of explosives in well-structured ambushes, although there is nothing new about such tactics," he said. "Iraq has, however, provided a unique opportunity for insurgents and Islamist extremists to make extensive use of IEDs by exploiting that nation's massive stocks of arms."

The attackers also learned to combine the extensive use of low grade IEDs, more carefully targeted sophisticated IEDs and very large car bombs to create a mix of threats and methods much more difficult to counter than reliance on more consistent types of bombs and target sets, Cordesman wrote in a study on the developing Iraqi insurgency.

Furthermore, suicide bombings in Iraq have a major psychological impact and gain exceptional media attention even though they are not tactically necessary. The same explosion could be achieved by remote control, Cordesman added.

Iraqi insurgents soon found that dispersed attacks on logistics and support forces often offer a higher chance of success than attacks on combat forces and defended sites.

At the same time, the insurgents realized that it is a lot easier to kill Iraqi officials and security personnel, and their family members than Americans, Cordesman said. "They also found it was easier to kill mid-level officials than better-protected senior officials," he wrote.

Insurgents have been adept at learning the behavior of U.S. forces and their Iraqi counterparts. Therefore, they have been exploiting slow Iraqi and U.S. reaction times at the local tactical level, particularly in built up areas.

"They learn to attack quickly and disperse," Cordesman said. Insurgents also take "advantage of any tendency to repeat tactics, security, movement patterns and other behavior; find vulnerabilities and attack."

A key area of vulnerability insurgents have been able to focus on is U.S. dependence on Iraqi translators and intelligence sources, he added.

Weak points in the U.S. military structure are human intelligence, battle damage assessment and damage characterization, Cordesman contended. "Iraqi insurgents and other Islamist extremists learned that U.S. intelligence is optimized around characterizing, counting and targeting things, rather than people," he said. "The United States has poor capability to measure and characterize infantry and insurgent numbers, wounded and casualties."

Back in the United States, the Combating Terrorism Technology Task Force, chaired by Riley, has been working with industry to fill some of the gaps in technology that would ultimately aid human intelligence. United States needs an end-to-end conceptual architecture for counter-insurgency operations and IED defeat together with a systems analysis, engineering and integration discipline, according to the task force.

Intelligence capability enhancements top the needs list. Information operations and intelligence, including cultural and political intelligence, should be integrated. The U.S. military also needs increased capabilities to exploit captured enemy systems, Riley said in a presentation to industry.

Among critical research needs are data management and retrieval capabilities, data fusion and language translation enhancements, predictive behavioral analysis and enemy pattern assessment capabilities, the integration of cultural and anthropological factors into intelligence analysis and decision-making, and anticipatory understanding of who will oppose stabilization efforts.